<template>
  <header class="header">
    <h1>todos</h1>
    <input id="toggle-all" class="toggle-all" type="checkbox" v-model="isAllFn">
    <label for="toggle-all"></label>
    <input
      class="new-todo"
      placeholder="输入任务名称-回车确认"
      autofocus
      @keydown.enter="addFn"
      v-model="task"
    />
  </header>
</template>

<script>
export default {
  data () {
    return {
      task:''
    }
  },
  props: ['list'],
 computed: {
  isAllFn: {
    set(val){
      this.list.forEach(item=>item.isDone = val)
    },
    get() {
      return this.list.every(item=>item.isDone)
    }
  }
 },
  methods: {
    addFn(){
      if(this.task.trim()===''){
        alert('不能为空')
        return
      }
      this.$emit('add',this.task)
      this.task=''
    }
  }
}
</script>